Accumulated Other Comprehensive Loss (Accumulated Other Comprehensive Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Aug. 31, 2012		Aug. 31, 2011		Aug. 31, 2012		Aug. 31, 2011
Schedule of Accumulated Other Comprehensive Loss [Line Items]
Balance as of February 29, 2012					$ (62,459)
Amortization recognized in net pension expense	189	[1]	103	[1],[2]	449	[1]	158	[1],[2]
Effective portion of changes in fair value	6,465	[3]	(6,487)	[2],[3]	4,634	[3]	(10,612)	[2],[3]
Reclassifications to CarMax Auto Finance income	730	[4]	975	[2],[4]	3,965	[4]	2,095	[2],[4]
Balance as of August 31, 2012	(53,411)				(53,411)
Unrecognized Actuarial Losses [Member]
Schedule of Accumulated Other Comprehensive Loss [Line Items]
Balance as of February 29, 2012					(39,774)
Amortization recognized in net pension expense					449
Balance as of August 31, 2012	(39,325)				(39,325)
Unrecognized Hedge Losses [Member]
Schedule of Accumulated Other Comprehensive Loss [Line Items]
Balance as of February 29, 2012					(22,685)
Effective portion of changes in fair value					4,634
Reclassifications to CarMax Auto Finance income					3,965
Balance as of August 31, 2012	$ (14,086)				$ (14,086)

[1] Net of tax of $111 and $14 for the three months ended August 31, 2012 and 2011, respectively; and $151 and $72 for the six months ended August 31, 2012 and 2011, respectively.

[2] As discussed in Note 2, fiscal 2012 reflects the revisions to correct our accounting for sale-leaseback transactions.

[3] Net of tax benefit of $9,845 and $4,218 for the three months ended August 31, 2012 and 2011, respectively; and $11,026 and $6,506 for the six months ended August 31, 2012 and 2011, respectively. The three months and six months ended August 31, 2012, include a tax benefit adjustment of $8,518 related to prior years.

[4] Net of tax of $2,563 and $0 for the three months ended August 31, 2012 and 2011, respectively; and $2,563 and $0 for the six months ended August 31, 2012 and 2011, respectively. The three months and six months ended August 31, 2012, include a tax provision adjustment of $1,270 related to the first quarter of fiscal 2013.